SUB-AREA FCID ALLOCATION SCHEME

• US 20110219183A1
• Filed: 03/03/2010
• Published: 09/08/2011
• Est. Priority Date: 03/03/2010
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Balasubramanian, Hariharan, Goyal, Ankur, SASSO, CHRISTIAN, Desai, Ronak, Kasat, Siddharth
• Granted Patent: US 9,632,930 B2
• Time in Patent Office: Days
• US Class Current: 711/108
• CPC Class Codes: G06F 12/06 Addressing a physical block of locations, e.g. base addressing, module addressing, memory dedication G06F12/08 takes precedence
• CPC Class Codes: G06F 15/173 using an interconnection network, e.g. matrix, shuffle, pyramid, star, snowflake
• CPC Class Codes: H04L 12/56 Packet switching systems
• CPC Class Codes: H04L 2101/645 Fibre channel identifiers
• CPC Class Codes: H04L 49/357 Fibre channel switches
• CPC Class Codes: H04L 61/5038 for local use, e.g. in LAN or USB networks, or in a controller area network [CAN]
• CPC Class Codes: H04L 67/1097 for distributed storage of data in networks, e.g. transport arrangements for network file system [NFS], storage area networks [SAN] or network attached storage [NAS]

Abstract

Certain embodiments of the present disclosure generally relate to allocating a sub-area of Fibre Channel addresses (FCIDs) to a device. A range of addresses may be assigned to the device using a mask address, where the most significant bits represent a mask and the least significant bits represent a sub-range of FCIDs available to be assigned to the device. Therefore, routing information may be stored efficiently in a Ternary Content Addressable Memory (TCAM) by storing a single entry in the TCAM for each sub-area of FCIDs allocated to a device, instead of storing an entry for each FCID. The single entry may indicate the mask address and the width of the mask.

Claims

1. A method for communication in a Fibre Channel Network, comprising:

receiving a request from a device to login to a switch;

allocating a range of Fibre Channel addresses (FCIDs) to the device; and

generating a single entry in a memory indicating the range of FCIDs.

2. The method of claim 1, further comprising:

receiving a fabric discovery (fdisc) request from the device; and

assigning one of the FCIDs of the allocated range to the device.

3. The method of claim 2, further comprising:

allocating an additional range of FCIDs to the device if the device has used all of the FCIDs in the allocated range; and

generating a second entry in the memory indicating the additional range of FCIDs.

4. The method of claim 1, wherein the range of FCIDs comprises 32 FCIDs.

5. The method of claim 1, wherein size of the allocated FCID range is different for different devices.

6. The method of claim 5, wherein size of the allocated FCID range is different in different allocations for the device.

7. The method of claim 1, wherein the memory is a ternary content addressable memory (TCAM).

8. A switch, comprising:

a processor; and

a memory containing a program configured to communicate in a Fibre Channel Network, which, when executed on the processor performs an operation, comprising;

receiving a request from a device to login to the switch;

allocating a range of Fibre Channel addresses (FCIDs) to the device; and

generating a single entry in another memory indicating the range of FCIDs.

9. The switching device of claim 8, wherein the operation further comprises:

receiving a fabric discovery (fdisc) request from the device; and

assigning one of the FCIDs of the allocated range to the device.

10. The switching device of claim 9, wherein the operation further comprises:

allocating an additional range of FCIDs to the device if the device has used all of the FCIDs in the allocated range; and

generating a second entry in the memory indicating the additional range of FCIDs.

11. The switching device of claim 8, wherein the range of FCIDs comprises 32 FCIDs.

12. The switching device of claim 8, wherein size of the allocated FCID range is different for different devices.

13. The switching device of claim 12, wherein size of the allocated FCID range is different in different allocations for the device.

14. The switching device of claim 8, wherein the other memory is a ternary content addressable memory (TCAM).

15. A computer-readable storage medium, containing a program, which, when executed on a processor is operable to:

receive a request from a device to login to a switch;

allocate a range of Fibre Channel addresses (FCIDs) to the device; and

generate a single entry in a memory indicating the range of FCIDs

16. The computer-readable storage medium of claim 15, further operable to:

receive a fabric discovery (fdisc) request from the device; and

assign one of the FCIDs of the allocated range to the device.

17. The computer-readable storage medium of claim 16, further operable to:

allocate an additional range of FCIDs to the device if the device has used all of the FCIDs in the allocated range; and

generate a second entry in the memory indicating the additional range of FCIDs.

18. The computer-readable storage medium of claim 15, wherein the range of FCIDs comprises 32 FCIDs.

19. The computer-readable storage medium of claim 15, wherein size of the allocated FCID range is different for different devices.

20. The computer-readable storage medium of claim 15, wherein size of the allocated FCID range is different in different allocations for the device.